Participatory Plant Breeding and Agroecology to Develop Intermediate Wheatgrass for Sustainable Grain Production

Participatory Plant Breeding and Agroecology to Develop Intermediate Wheatgrass for Sustainable Grain Production

Summary

Perennial crops that live for many years increase sustainability by holding soil, reducing nutrient runoff, limiting pesticide use, and boosting farmer incomes through a decrease in inputs. All commonly grown grain crops are annuals, but we are working to develop intermediate wheatgrass (IWG), which has potential to become the first widely grown perennial grain crop.
This project will develop improved IWG plants and determine the effect of nitrogen fertility on sustained grain yield in IWG.
We are conducting a participatory plant breeding program that includes growing IWG on college campuses, on an NGO research station in Kansas, and at a commercial nursery in Wisconsin in order to identify superior genotypes. Through cross-pollination, we are combining several important traits that we have discovered: large seed, shortness, and shatter resistance. To answer the key question of the role of soil nitrogen (N) in sustained yield, a range of N addition treatments have been applied to IWG stands on three on-farm fields and at research stations in Kansas and Minnesota. Plant tissue nitrogen and seed yield traits are being measured.
Results from the proposed research will be published in peer-reviewed journals, reported to the scientific community through seminars, published in the popular press (web and hard copy), and presented to several hundred yearly visitors to The Land Institute.

Objectives/Performance Targets

We expect the proposed project to contribute to the following outcomes:
• Increased knowledge of how to grow and breed IWG for use as a perennial grain crop. Through experimentation and interaction with members of the community of practice, we have been improving our methodology for growing and breeding IWG. We expect this trend to continue, which will be evidenced by accelerated progress in the breeding program and improved techniques for growing the crop.
• Increased optimism for the potential of IWG as a crop in the food and agriculture community. Optimism is essential to achieving expanded research, development, and planting of the crop. This optimism will be derived from clear progress in the breeding program and the discovery of reliable techniques for raising a productive crop.
• Increased scientific research with IWG throughout the north central United States. For a new crop to succeed, a diverse team of researchers must be assembled to work on the challenges as they arise. Interest from scientists in many fields is growing, and we soon hope to have a wide array of scientific collaborators.
• IWG is planted on a large acreage for commercial use, which reduces soil erosion on sloping lands. This is an intermediate term outcome. Commercial plantings depend upon the development of improved varieties, agronomic practices, processing techniques, and marketable products. We expect that even with sustained research funding, this outcome is at least 10 years away.
Short-term outcomes will include increased knowledge of how to grow and breed IWG, optimism for its potential as a crop within the food and agriculture community, and an increased number of scientists actively engaged in IWG research.
Intermediate outcomes will include widespread planting of IWG by farmers and commercial use of the grain for food. To evaluate, we will measure indicators of progress toward these outcomes.
In the long term, we anticipate that diverse perennial grain cropping systems could replace more than 50% of current annual crop acreage. Success in breeding, growing, processing, and marketing IWG will serve as a proof of concept for perennial grains in general. IWG will spark interest in and funding for many other perennial grains, including wheat, rice, sunflowers, dry beans, maize and sorghum. Wherever perennial grain crops are planted, soil erosion will be reduced below replacement levels, nitrate loss to ground and surface waters will be reduced by more than 90%, and herbicide contamination will be sharply reduced. Furthermore, reduced input costs will benefit farmers and rural communities economically.

Accomplishments/Milestones

Trials with nitrogen fertilizer rates ranging from zero to 200 lbs/acre were maintained. Biomass was most responsive on the farm with the loam soil. On the farm with sandy soil, water was limiting and therefore biomass was less responsive. But at both locations, response was linear through 200 lbs/acre. These results differ from the first year, when 100 lbs/acre N was adequate for maximum biomass yield.
Seed yield was essentially zero at all locations due to extreme drought several years in a row. Reduced N fertilizer application resulted in reduced biomass, which in term limited transpiration. Therefore, with reduced N, moisture was available longer into the growing season. However, this treatment was not adequate to achieve any measurable seed production.

We used controlled pollinations in the greenhouse to mate plants outstanding for seed size, seed yield, short stature, free threshing ability, earliness, and non-shattering. Seed of these plants were planted in small pots and transplanted to the field in fall 2011 to establish a new breeding nursery with about 14,000 individuals. We have kept track of both the male and female parents of every cross so that the performance of families as well as individuals could be used in making selections.
This year we again performed an additional cycle of bulked mass selection for large, naked seed. We used a robotic seed size sorter to select the largest seeds out of 29,000 naked seeds that were harvested from the previous generation. The largest 314 seeds were selected, and a new nursery was established fall 2012.
Approximately 1000 individuals were established during 2011 in Wisconsin. In 2012, seed was harvested from each of these plants, and selections were made based on yield, seed size, and threshability. Selected plants are being intermated to obtain an improved population for northern locations. Out of this population we also identified some plants with “white” seed. These are being intermated in hopes of creating a white-grain IWG type.

Data that was reported in 2011 has now been prepared into a manuscript for publication.

Impacts and Contributions/Outcomes

In recent years, IWG has been marketed at a very limited scale. Purchasers of flour have had mostly positive feedback, there has been desire expressed by many to have the flour available on a regular basis in local markets. For an example of one purchaser’s experience, see http://www.huffingtonpost.com/julie-brothers/kernza-flour-bread_b_1165936.html .
In the past year our annual outreach event was strong. Attendance was about 1,200 and it was described in the New York Times. See: http://www.nytimes.com/2012/10/03/us/prairie-festival-draws-crowds-to-land-institute-in-kansas.html?_r=0 A talk about progress with IWG was given to attendees, and field tours were also conducted.
In the past year germplasm and plant materials were distributed to collaborators at five research institutions, indication this work is continuing to catalyze additional research.

Collaborators: